Abstract: In a heterogeneous network environment a method of selecting an access router (20) among a number of available access routers (20, 22, 24) for a group of mobile network nodes (14) attached to a mobile router (12), each access router (20, 22, 24) providing access to packet-switched resources in a respective network domain (26, 28, 30) and each mobile network node (14) having a desired QoS level at the network layer, which method comprises the steps of: (a) determining a group QoS level acceptable to substantially all mobile network nodes (14) in said group; (b) using said group QoS level to query at least one of said number of respective network domains (26, 28, 30) to determine whether or not it can meet said group QoS level; and (c) using a response from said at least one network domain (26, 28, 30) to decide whether or not to perform a network layer handover of said group of mobile network nodes (14) to one of said number of available access routers (20, 22, 24).

Abstract: A method of providing access for a multi-mode mobile terminal (13) to packet-switched services in a heterogeneous network environment (10) comprising a uni-directional network (12) and a bi-directional network (11), which method comprises the step of creating and storing a data structure in each of said multi-mode mobile terminal (13), said bi-directional network (11) and said uni-directional network (12), storing of said data structures activating a logical association between said multi-mode mobile terminal (13) and said uni-directional network (11) via said bi-directional network (12), which logical association facilitates inter-working of said uni-directional and bi-directional networks for delivering datagrams to said multi-mode mobile terminal (13) from said uni-directional network (12).

Abstract: A diversity transmitter for use in an OFDM transmission protocol which diversity transmitter comprises: a diversity generator (2) for receiving and diversifying OFDM transmit symbols, and outputting diversified OFDM symbol matrices (DOSM), DOSM symbols within each DOSM being divided into at least two primary streams each comprising different DOSM symbols, a transmit processor for receiving said at least two primary streams of DOSM symbols, and for transforming said each DOSM symbol from the frequency domain into the time domain, and outputting time domain OFDM symbols (TDOSs), a cyclic delay circuit (41 . . . 4P) for dividing at least one of said primary streams of TDOSs into at least two branches of identical TDOSs, each branch for supplying a respective spatial channel for transmission to a receiver, the arrangement being such that, in use, said cyclic delay circuit (41 . . . 4P) applies a cyclic time shift to a TDOS symbol in at least one of said branches before transmission.

Abstract: A method of discovering multi-mode mobile terminals (13) in a heterogeneous network environment, each multi-mode mobile terminal (13) having at least one interface for sending packet data to and/or receiving packet data from a home radio communication network (11) and a foreign radio communication network (12), said home radio communication network having a different access technology from said foreign radio communication network, each multi-mode mobile terminal (13) performing the steps of: (a) listening to said foreign radio communication network (12); (b) receiving and storing a foreign network indicator for indicating presence of said foreign radio communication network (12); and (c) transmitting said foreign network indicator to said home radio communication network (11); whereby said home radio communication network (11) may store a database comprising a mapping between a multi-mode mobile terminal identity, a home network indicator and a foreign network indicator, to facilitate interworking o

Abstract: A method of routing data packet flows from a mobile router in a mobile network, which mobile network comprises one or more network node attached to said mobile router, said mobile router for providing transparency at the network layer for said one or more network node to movement of said mobile network relative to a fixed network infrastructure, which method comprises the steps of: (a) receiving a data packet from a first host within said mobile network addressed to a second host; (b) estimating which type of traffic is present in said data packet; and (c) forwarding said data packet by applying a first routing method for a first type of traffic and a second routing method for a second type of traffic.

Abstract: A method of reducing packet congestion at a network node in a packet-switched data communication network, which method comprises the steps of marking one or more packets in said queue, wherein a probability of marking a packet in the queue is higher for a first proportion of the packets than for a second proportion of the packets, one or more packets of said first proportion having spent less time on said network than one or more packets of said second proportion.

Abstract: A method of discovering a contact identifier by which data may be sent over one or more electronic data communication network (10) toward one or more network access device (14-20) used by a user (21), which method comprises the steps of: (a) electronically collecting a contact identifier from said one or more network access device, and storing said contact identifier in memory, which contact identifier provides an indication of the addressing option(s) available on the or each network access device; (b) generating an electronic database comprising or comprising a reference to said contact identifier; and (c) providing access to said electronic database whereby said user (21) and/or another user may obtain said contact identifier, whereby said user and/or another user may discover said addressing option(s) to facilitate transmission of data toward said one or more network access device (14-20).

Abstract: A method of operating a cellular communications system comprising at least one macro cell having a macro cell base station and at least one micro cell having a micro cell base station, at least part of the micro cell being located within an area served by the macro cell base station, which method comprises the steps of: (I) receiving an electronic indication representative of the quality of service at one or more cellular communications devices served by the macro cell base station; (2) electronically processing the or each electronic indication to obtain a comparison with a predetermined threshold for said quality of service; and (3) electronically controlling signals emitted from the micro cell base station in response to said comparison such that the quality of service of any cellular communication device(s) served by the macro cell base station that are within a predetermined range of the micro cell base station exceeds said predetermined threshold so as to permit the transmission and reception of data in